Solution: Visit www.speedguide.net/downloads.php. The TCP Optimizer is a free, easy Windows program that provides an intuitive interface for tuning and optimising your Internet connection. No installation is required. The program makes it easy to find the best MTU and RWIN values, test latency, and tweak all the important registry parameters. This application can be helpful with tuning any Internet connection type, from dialup to Gigabit+.